Friday, January 26, 2007

Nomad Build: Fitting the Fork






As well as the fork and frame you will need a plastic or rubber mallet, a pipe cutter, pencil, coarse silicon carbide sandpaper and a high quality bicycle grease preferably in a grease gun.

Make sure the headset is pressed squarely into the frame, we recommend getting a shop to do this as without the specific tools it is not only difficult but can very easily go wrong resulting in irreparable damage to the frame.

Tap the bottom ring of the headset onto the fork steerer tube with the plastic mallet. Do this gently working your way around the ring with constant tapping. The steerer tubes are often flared near the fork brace so will need additional tapping at this point. It is essential to ensure that the ring sits squarely against the fork brace. Apply a bead of grease around both the ring on the steerer and inside the headset lower bearing race. Insert the steerer tube into the bottom headset race and slide it home applying grease to the steerer tube will make it slide through the headset more easily. Rest the front wheel on the ground and tap the upper headset ring down the steerer tube with the plastic mallet, go gently and keep taping all the way round, it is essential that the race sits squarely against the upper bearing race of the headset.

Fit both wheels, seatpost and saddle to the bike and then stem/handlebar, use the appropriate number of spacers to get a comfortable height. We recommend changing the height a couple of times and even going for a couple of short rides to make sure you get a comfortable stem/handlebar height, the next step involves cutting the steerer tube to length.

After the getting a comfortable stem/handlebar height use a pencil to mark the steerer tube 1cm above where you think it needs to be cut (this will provide height adjustment after the steerer tube is cut). Remove the fork from the frame. It is essential not to get any dirt or metal swarf into the headset during the cutting process. Turn the fork upside down and either clamp the steerer in a bike stand, rest the steerer upside down on the floor or get a friend to hold it upside down. Attach the pipe cutter to the steerer and tighten it very gently onto the tube, rotate it slowly and it will begin to score and then cut the steerer. As it cuts it will feel loose, again tighten gently and keep rotating. When it has almost cut through the tube tighten it very very gently until it cuts all the way through. Use a clean rag a wipe the steerer tube thoroughly with degreaser and make sure there are no pieces of metal debris left on either the outside or inside of the tube. Use the sandpaper to remove all traces of burr on both the outside and inside of the tube. Cut the steerer very slowly and carefully and don't be tempted to crank the cutter tight against the tube, care at this stage means less de-burring in the next step!

Refit the fork, headset top ring, appropriate spacers, stem/handlebar and the front wheel, hammer the star-fangled nut about 25- 30 mm into the steerer tube and screw down the headset cap ensuring the front wheel is square with the handlebar.

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